Azodyestuffs



7 Patented Jan. 7, 1936 .cmet s'TA'TEs;

was

PATENT OFFICE.

2,026,920 AZODYESTUFFS Carl Taube, Leverkusen-I.

Hilger, signors to Leverkusen-Wiesdorf, Germany, General Aniline Works, Inc., York, N. Y., a corporation of Delaware G.-Werk, and Josef as- New No Drawing. Application October 12, 1933, Serial In Germany November 5, 1932 4 Claims. (01. 260-84) The present invention relates to stuffs, more particularly it relates which maybe represented eral formula:

new azodyeto dyestuifs by the probable gen- SIOaH OH l halogen NHac wherein the benzene nucleus R may be substineutral medium with formula:

HaCIJ S blH V H? 01-N=NON=N- a (3m HOIS/ Nn-o 0-6 tuted by further substituents, such as alkyl, R1 stands for a radical of the benzene series to which the azo bridges are attached in para-position to each other, such as a benzene nucleus which may be substituted, for example by alkyl, alkoxy and halogen, and ac stands for an acyl radical, such as acetyl, benzoyl and a urea radical.

Our new dyestuffs are obtainable by diazotizing a ZA-dihaIOgen-aniline-6-sulfonic acid, coupling in an acid medium with a middle component of the benzene series coupling in para-position with respect to the amino group, further diazotizing and coupling with a 2-acylamino-5-naphthol-l-sulfonic acid. Favorably the middle component is coupled in form of its N -w-methane sulfonic acid, the wmethane sulfonic acid radical being split off prior to the further diazotization and last coupling.

- Our new dyestufls are in form of their alkali metal salts generally red to dark powders, soluble in water, dyeing the cellulosic fibre generally red to violet shades of good fastness to light.

The invention is illustrated .by the following examples, without being limited thereto:

Example 1.'30 parts by weight of the potassium salt of 1-amino-2,4-dichloro-5-methylbenzene-G-sulfonic acid are dissolved in water to a clear solution. The calculated quantity of sodiis isolated in the usual dried. It dyes cotton clear red shades. 7

By substituting the m-toluidine by corresponding quantities of 1-methoxy-2-amino-4-methylbenzene or by 1-methyl-3-amino-4:-chlorobenmanner by salting out and from a Glaubers salt bath properties.

Example 2.41 parts by weight of the potassium salt of 2,4-dichl0roaniline-6-su1f0nic acid are dissolved in 1100 parts by weight of water at room temperature, 10 parts by weight of sodium nitrite are added, and the clear solution is acidifled with hydrochloric acid. The diazonium chloride separates in beautiful colorless crystals dyes cotton from a Glaubers salt bath clear red shades of excellent fastness to light.

A dyestuff having similar properties is obtained when using as final coupling component the symzene, there are obtained dyestufi's having similar bromoaniline-G-sulfonic acid there is obtained a general formula:

metrical urea of the 2-amino-5-naphthol-7-su1- fonic acid.

Example 3.10 parts by weight of the potassium salt of 2,4-dichloroaniline-G-sulfonic acid are dissolved in water, 2,4 parts by weight of sodium nitrite are added thereto, and the solution is acidified with hydrochloric acid. The diazo compound is coupled in weakly Congo acid solution with para-xylidine, the bright red precipitate is isolated, dissolved in water with the aid of ammonia, the calculated quantity of sodium nitrite is added to the solution, and the same is substituted by alkyl, R1 stands for a benzene nucleus to which the azobridges are attached in para-position to each other and which may bear substituents selected from the group consisting of alkyl, alkoxy and halogen and ac stands for an acyl radical, being in form of their alkali metal salts generally red to dark powders, soluble in water, dyeing the cellulosic fibre generally red to violet shades of good fastness to light.

3. Azodyestuffs having in the free state the general formula:

acidified by hydrochloric acid. The diazonium 1 OH compound separated is filtered with suction and h 1 R coupled in a weakly acid medium with 2-acetyla ogen 1 amino-S-naphthol-l-sulfonic acid. The dyehalogen NH ac stuff obtained having in its free state the folnols lowmg formula: wherein the benzene nucleus R may be further (ll on, NH-OC- CH:

HOiS

dyes cotton a bluish-red of excellent fastness to substituted by alkyl, R1 stands for a benzene nucleus to which the azobridges are attached in para-position to each other and which may bear light.

By substituting the 2,4-dichloroaniline-6-sulfonic acid by an equivalent quantity of 2,4-didyestufi having similar properties.

We claim:

1. Azodyestufis having nlkyl, alkoxy and halogen and ac stands for an acyl radical of the group consisting of acetyl,

in the free state the benzoyl and a urea radical, being in form of SOiH O n l l halogen-@-N=N-Ih-N=N-@ l h 10 en NH-ac a g nols wherein the benzene nucleus R may be substituted powders, soluble in water, dyeing the cellulosic fibre generally red to violet shades of good lastness to light.

4. The azodyestuff having in the free state the following formula:

by alkyl, R1 stands for a radical of the benzene series to which the azobridges are attached in para-position to each other and ac stands for I an acyl radical, being in form of their alkali NH-oC-on. metal salts generally red to dark powders, soluble in water, dyeing the cellulosic fibre generally red to violet shades of good fastness to light.

2. Azodyestuffs having in the free state the general formula:

dyeing cotton from a Glaubers salt bath clear red shades of excellent fastness to light.

CARL TAUBE.

J OSEF HILGER.

llalogen NH-ac substituents selected from the group consisting of their alkali metal salts generally red to dark 

